pef2256e Infineon Technologies Corporation, pef2256e Datasheet - Page 191

• Manufacturer Part Number: pef2256e
• Description: E1/t1/j1 Framer And Line Interface Component For Long- And Short-haul Applications
• Manufacturer: Infineon Technologies Corporation

5.6.4
The local loop-back mode, selected by LIM0.LL = 1, disconnects the receive lines RL1/2
or RDIP/RDIN from the receiver. Instead of the signals coming from the line the data
provided by system interface are routed through the analog receiver back to the system
interface. However, the bit stream is transmitted undisturbedly on the line. An AIS to the
distant end can be enabled by setting FMR1.XAIS without influencing the data looped
back to the system interface.
Note that enabling the local loop usually invokes an out of frame error until the receiver
resynchronizes to the new framing. The serial codes for transmitter and receiver have to
be identical.
Figure 78
User’s Manual
Hardware Description
RL1
RL2
XL1
XL2
Local Loop
Local Loop (T1/J1)
MUX
Clock +
Data
Recovery
AIS-GEN
RCLK
191
Rec.
Framer
Trans.
Framer
Functional Description T1/J1
Elast.
Store
Elast.
Store
DS1.1, 2003-10-23
PEF 2256 H/E
ITS09749
RDO
XDI
FALC
®
56